Cylinder wall reboring tool



F. SVAB CYLINDER WALL REBORING TOOL Dec. 3, 1940.

Filed July 2'7, 1939 2 Sheets-5heet l Inventor A itomeys Dgc. 3, 1940. E. F. svAB CYLINDER WALL REBORING TOOL Filed July 27, 1939 2 sheets sheet 2 w w 2. o o p 2 f 2 M M ii A m 6 v L I 0 OH. a 1 A L 4 a M 1 d 0 6 u \,\I v\ A ttomeys Patented Dec. 3, 1940 UNITED STATES PATENT OFFICE l 2,223,582

CYLINDER WALL REBORING TOOL Edward F. Svab, Hudson, Ohio Application July 27, 1939,'Serial No. 2865914 2 Claims.

This invention relates to a cylinder Wall reboring tool of the character set forth in my U. '8. Letters Patent granted July 2 0, .1937, and numbered 2,087;823,'and has for the primary object the provision of an improved means for adjusting the blade to make a desired cut and which permits the blade to be adjusted at any time during the reboring operation without removing the device from the cylinder, consequently permitting more accurate boring of the cylinder to be accomplished with the complete boring operation carried out within a minimum length of time and with the least amount of manual effort.

With these and other objects in View, the invention consists in certain novel features of construction, combination and arrangement of parts to be hereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be had to the following description and accompanying drawings, in which- Figure 1 is a side elevation illustrating a cylinder wall reboring tool constructed in accordance with my invention.

Figure 2 is a top plan View illustrating the same.

Figure 3 is a vertical sectional view showing the means of adjusting the blade.

Figure 4 is a perspective view illustrating the blade.

Figure 5 is a perspective View illustrating one of the equalizing blocks for the mandrel.

Figure 6 is a perspective View illustrating one of the auxiliary spacing blocks or strips.

Referring in detail to the drawings, the numeral 5 indicates a mandrel, the length of which is slightly greater than the height of the cylinder to be rebored and is provided adjacent its upper end with oppositely arranged openings to permit a bar 6 to extend through the mandrel to act as a handle. The mandrel has a substantially cylindrical exterior shape and a semi-cylindrical interior shape presenting a flat face 1. Cast integral with the exterior of the mandrel 5 is an offset 8 providing a blade holder and is provided with an arcuately curved outer face. The mandrel Within its flat face 7 is provided with screw threaded sockets 9 to receive set screws H], the heads of which are arranged upon the interior of the mandrel. The offset portion 8 has formed therein a blade slot ll arranged at a desired inclination and opening outwardly through the arcuately curved face of the blade holder and communicating with the sockets 9 by having the blade slot to extendwell within the wall of the mandrel, as shown in Figure 3.

The set screws are adjusted from within the mandrel, the latter having openings l2 opposite the 'set screws to permit a screw driver or like 5 'tool to enter the mandrel and engage with the 'set screws to bring about the adjustment thereof.

A blade l3 having a cutting edge M of hook shape is slidably received within the blade slot l I with the cutting edge projecting well beyond the 10 arcuately curved face of the blade holder 8.

The blade I3 is free to slide inwardly and outwardly as Well as endwise of the blade slot H and the edge thereof opposite to the cutting edge I4 is provided with notched portions l5 each de- 15 fining a pair of cam faces l6 and I1 sloping in opposite directions from each other to form. a high point l8 and stop shoulders [9 at each end of the cam. faces. The set screws enter the notches to engage the cam faces, as clearly shown 20 in Figure 3, and by adjusting the set screws the blade may be adjusted outwardly with respect to the mandrel to a desired distance. An end wall of the blade holder 8 has threaded therein a set screw 20 to engage with one end of the blade, the 25 purpose of which is to adjust the blade endwise by coacting with the set screws [0.

Spacing blocks 2i are secured on the outer faces of the mandrel and spaced an equal distance from each other and from the blade holder 30 and coact with the latter in centering the mandrel within a cylinder. The spacing blocks 2! have formed upon their upper ends right angularly disposed stops or extensions 22 for limiting the downward movement of the mandrel into the cylinder.

Auxiliary spacer strips or blocks, as shown in Figure 6 and indicated by the character 23, may be positioned between the spacer blocks 2| .and the body 5 of the tool when it is desired to adapt 40 the tool for use in cylinders having larger bores.

In operation, the mandrel with the handle 6 applied thereto is placed in the cylinder with the stops 22 coming to rest on the upper end of the cylinder. Prior to the placing of the mandrel in the cylinder the set screws II] are adjusted to bring about adjustment of the blade on the mandrel in an outward direction therefrom so as to leave a slight clearance between the cutting edge of the blade and the wall of the cylinder when the mandrel is inserted therein. The set screw 20 is then rotated to slide the blade downwardly which also brings about an outward movement of the blade by the cam faces riding the set screws l0 bringing the blade in cutting contact with the walls of the cylinder so that on rotation of the mandrel by the handle the walls of the cylinder will be rebored to a determined measurement with the least expenditure of manual efi'ort.

It is believed that the foregoing description, when taken in connection with the drawings will fully set forth the construction and advantages of this invention to those skilled in the art towhich such a device relates, so that further de-- tailed description will not be required.

What I claim is:

1. In a device of the character set forth comprising a mandrel, a blade holder cast integral with said mandrel and including a blade slot extending well into the walls of the mandrel, said holder having an arcuately curved face, spacing blocks secured on the exterior of the mandrel and having arcuately curved faces, a blade of a length less than the length of said slot mounted in said slot, said blade includinga hook-shaped cutting edge and having spaced notches in an edge of the blade opposite tothe cutting edge and each notch defining cam faces extending in opposite directions with a high portion between said faces, set screws threaded in said mandrel to engage the cam faces, and a set screw threaded in one end of the holder to engage with one end of the blade to coact with the first-named set screws in adjusting the blade outwardly of the holder and endwise of said holder.

2. In a device of the character set forth comprising a mandrel, a blade holder cast integral with said mandrel and including a blade slot extendin well into the walls of the mandrel, said holder having an arcuately curved face, spacing,

blocks secured on the exterior of the mandrel and equally spaced from each other and from the blade holder and having arcuately curved faces, a blade of a length less than the length of said slot mounted in said slot, said blade including a hook-shaped cutting edge and having spaced notches in an edge of the bladeopposite the cutting edge and defining cam faces, set screws threaded in said mandrel to engage the cam faces, and a set screw threaded in one end of I EDWARD F. svAB. 

